180 THE BOOK OF CHOICE FERNS. 



and fertile ; others with barren fronds sometimes simple but forked, or 

 pinnatifid (the divisions of the pinnae not extending quite to the stalk 

 or rachis) or pinnate at the base when fully developed ; some species also 

 copiously pinnate, and even doubly pinnate. Main veins none, or indistinct. 



Egenolfia (Eg-en-olf'-i-a), Schott. — The characters peculiar to the plants 

 belonging to this group differ from those belonging to Polybotrya (Pol-yb-ot'-ry-a) 

 only through the presence of a seta (bristle) in the sinus (depression) of the 

 lobes of the ultimate divisions. 



Elaphoglossum (El-aph-og-los'-sum), Schott. — An important group, com- 

 prising numerous species with fronds either simple or pinnate, and veins 

 free ; the barren fronds of some species being nearly or quite naked, the 

 edge not fringed ; others, with both surfaces also nearly or quite naked, 

 have the edge of their fronds fringed ; some, again, have the upper surface 

 of their fronds slightly, and others densely, scaly. 



Gymnopteris (Gym-nop'-ter-is), Bernhardt. — Ferns belonging to this 

 group are peculiar through the dimorphous nature of their fronds, which 

 in some species are entire, and in others sometimes simple, but with one or 

 two pairs of pinnae when fully developed ; in other cases, copiously pinnate. 

 Veins copiously anastomosing, the main vein being distinct, and extending 

 nearly or quite to the edge. 



Hymenolepis (Hym-en-oF-ep-is), Kaulfuss. — Plants with simple, uniform 

 fronds, bearing the fruit on the contracted apex (point). 



Oleersia (Ol-fer'-si-a), Raddi. — Fronds pinnate, with veins anastomosing, 

 and united only near the margin. 



Phottnopteris (Pho-ti-nop'-ter-is), /. Smith. — Ferns with pinnate or 

 deeply-pinnatifid (divided nearly to the midrib) fronds, easily distinguished 

 through the fruit being disposed on the Lomaria-like upper pinnae. 



Polybotrya (Pol-yb-ot'-ry-a), Humboldt and Bonpland. — Plants with 

 barren fronds variously pinnate and pinnatifid, but not of Lomaria-like habit ; 

 veins pinnate in the ultimate divisions of the fronds, except in A. (P.) bifur- 

 catum (bif-ur-ca'-tum), where a single vein is carried into each ultimate 

 division. 



Rhipidopteris (Rhi-pid-op'-ter-is), Schott. — A small group of plants with 

 venation flabellate (fan-shaped) ; fertile fronds small, sub-orbicular (nearly 

 round), and uncut. 



